The MS EQ using the S-curve and further tweaks that Wesayso suggested are all big improvements to the phantom center. Filling in that 1.8 kHz stereo dip makes a big difference in the center phantom tonality. It also tremendously improves imaging. Everyone should try it out for themselves.
Another thing I've been listening to is the attached phase curve. It is a 45 deg delta between L and R from 1 kHz to about 6 kHz. I was trying to recreate what I'd heard in the earlier 'phasey' correction. Unlike the phase shuffler in Rephase, this keeps the phase delta flat through the 1-6 kHz region. I am finding that this has a positive influence on imaging. Wondering if someone else can try it and report back. You can make that in Rephase and then convolve that with the regular FIR correction (if you use one) using the sox fir command.
Another thing I've been listening to is the attached phase curve. It is a 45 deg delta between L and R from 1 kHz to about 6 kHz. I was trying to recreate what I'd heard in the earlier 'phasey' correction. Unlike the phase shuffler in Rephase, this keeps the phase delta flat through the 1-6 kHz region. I am finding that this has a positive influence on imaging. Wondering if someone else can try it and report back. You can make that in Rephase and then convolve that with the regular FIR correction (if you use one) using the sox fir command.
Attachments
I’ve skipped around on this thread a bit so I apologize if this has already been covered but I was thinking about the phantom center comb filtering as it affects two speaker playback of a monophonic LP even when played back with a mono phono cartridge. Is this a special case that can be fixed with phase shuffling via a DSP module or is this subjectively an unsatisfactory solution?
I actually like mono better out of two speakers than out of one speaker. At least for large scale works. For TV dialog it's different because of the dips right in some important vocal frequencies. A single speaker often works best for dialog.
The shuffler and EQs discussed in this thread will work the same on a mono signal as stereo, because the effect is tied to the phantom center and that's the mono part of the signal. Even in full mono, it should give a more consistent tonal balance. However, with no left to right panning, it probably won't be noticeable in mono as it is in stereo, though you should notice a brightening of the tonal balance. It will be up to you to decide if that sounds right or not.
The shuffler and EQs discussed in this thread will work the same on a mono signal as stereo, because the effect is tied to the phantom center and that's the mono part of the signal. Even in full mono, it should give a more consistent tonal balance. However, with no left to right panning, it probably won't be noticeable in mono as it is in stereo, though you should notice a brightening of the tonal balance. It will be up to you to decide if that sounds right or not.
I've noticed that phantom center in music is less often as solid as when watching a video on youtube or seeing a movie on netflix. I simply experience that the sound seems to emit directly from the screen and I almost totally forget my speakers while watching.
My conclusion is that my system can create a very solid an convincing phantom center - but that the source material really needs to be of a certain quality.
After I build my speakers to have a more narrow baffle by giving it an angle-like bevel-cut, the image was even better. Measurements confirmed this - cause off-axis was now way smoother and looked much more like the on-axis.
My first inspiration was Avalon speakers, but I made the cut closer to the drivers and used a small waveguide and small midrange - Seas DXT + 5".
I've heard many narrow dispersion speakers..... but even though they can play with a very sharp image, they can be a little to much with sitting close to them - even if a house-curve is used. A little reflection seems to create a comfy space - but no to much..... pheww... a fine balance
My conclusion is that my system can create a very solid an convincing phantom center - but that the source material really needs to be of a certain quality.
After I build my speakers to have a more narrow baffle by giving it an angle-like bevel-cut, the image was even better. Measurements confirmed this - cause off-axis was now way smoother and looked much more like the on-axis.
My first inspiration was Avalon speakers, but I made the cut closer to the drivers and used a small waveguide and small midrange - Seas DXT + 5".
I've heard many narrow dispersion speakers..... but even though they can play with a very sharp image, they can be a little to much with sitting close to them - even if a house-curve is used. A little reflection seems to create a comfy space - but no to much..... pheww... a fine balance
Listening to mono mixes of recordings from the mid/late 60s and earlier with a stereo pair of constant directivity speakers produces a very stable center image. I prefer it to listening through my actual center channel because my center channel is much below ear level and in many respects, my L & R loudspeakers are less compromised than my center channel.
Just a reminder, the idea behind the phase shuffler or M/S EQ isn't to make a more stable phantom image, but to make a phantom center that has the same tonal balance as a single speaker playing alone.
If that results in a more stable phantom center, then it's a happy side effect.
I don't remember experiencing that on my system, but others have reported that they did.
If that results in a more stable phantom center, then it's a happy side effect.
I don't remember experiencing that on my system, but others have reported that they did.Hey guys,
There is an impressive dsp cat at the following link that I think is doing impressive work in this area. Check it out and see what you think:
Revisiting stereo shuffling - DSP, Room Correction, and Multi Channel Audio - Audiophile Style
English - Home Audio Fidelity
Bill
There is an impressive dsp cat at the following link that I think is doing impressive work in this area. Check it out and see what you think:
Revisiting stereo shuffling - DSP, Room Correction, and Multi Channel Audio - Audiophile Style
English - Home Audio Fidelity
Bill